[PATCH 2/5] Use SecureZeroMemory on windows for explicit_bzero

[roucaries . bastien]

From: Bastien Roucariès <address@hidden>

Signed-off-by: Bastien Roucariès <address@hidden>
---
 lib/explicit_bzero.c | 7 +++++++
 m4/explicit_bzero.m4 | 5 +++++
 2 files changed, 12 insertions(+)

diff --git a/lib/explicit_bzero.c b/lib/explicit_bzero.c
index 862855421..b355f9bdf 100644
--- a/lib/explicit_bzero.c
+++ b/lib/explicit_bzero.c
@@ -32,6 +32,11 @@
 
 #include <string.h>
 
+#if defined WIN32 && defined HAVE_SECUREZEROMEMORY
+#define  WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#endif
+
 #if _LIBC
 /* glibc-internal users use __explicit_bzero_chk, and explicit_bzero
    redirects to that.  */
@@ -47,6 +52,8 @@ explicit_bzero (void *s, size_t len)
   explicit_memset (s, 0, len);
 #elif HAVE_MEMSET_S
   (void) memset_s(s,len,'\0',len);
+#elif HAVE_SECUREZEROMEMORY
+  (void) SecureZeroMemory(s,len);
 #else
   memset (s, '\0', len);
 # if defined __GNUC__ && !defined __clang__
diff --git a/m4/explicit_bzero.m4 b/m4/explicit_bzero.m4
index 3ca5dc771..8f3144342 100644
--- a/m4/explicit_bzero.m4
+++ b/m4/explicit_bzero.m4
@@ -19,6 +19,11 @@ AC_DEFUN([gl_FUNC_EXPLICIT_BZERO],
   if test $ac_cv_func_memset_s = no; then
     HAVE_MEMSET_S=0
   fi
+
+  AC_CHECK_FUNCS_ONCE([SecureZeroMemory])
+  if test $ac_cv_func_SecureZeroMemory = no; then
+    HAVE_SECUREZEROMEMORY=0
+  fi
 ])
 
 AC_DEFUN([gl_PREREQ_EXPLICIT_BZERO],
-- 
2.25.1